Famous American boxer Bill Richmond, known as the world's first black sports star, is also buried there, along with members of the Christie family who founded the famous auction house.

Archaeologists do know the St James burial ground, which was converted into St James's Gardens in the mid-1800s, was divided into four sections, with the wealthy being buried close to a chapel and the poor further back.

Some fear that the explorer who gave Australia its name could have been buried under London's original Euston station, where a statue in his honour stands, but on site there's hope archaeologists have not yet reached his final resting place.

"If he is here in a coffin, hopefully with a name plate, that would give us total confidence that we have found him," Ms Wass said.

Many of the name plates and tombstones have been completely preserved thanks to London's damp clay in which they were buried.

"The preservation is really good and we have got a lot of skeletons that have surviving coffin breast plates, and this is really useful because it can give us a name of an individual, a date that they died," said Mike Henderson, the senior human osteologist on the project.

More than 1,000 archaeologists and specialists are working on Britain's biggest-ever excavation, which extends along the fast train route from London to Birmingham.

In Birmingham another graveyard is being dug up and graves exhumed, while it is believed Roman settlements and medieval villages could also lie along the train route.

"It's the scale of this project that is really significant, so the number of skeletons we will excavate will really be able to help us build a picture of what life was like for this population," Mr Henderson said.

The HS2 train network will eventually run for 531 kilometres and link London to the East Midlands, Leeds and Manchester — but it has raised concern among communities along the route.

Ms Wass said all is being done to limit the damage and respect the dead.

"We are coming face to face with our ancestors and people who are buried here are dealt with dignity and care and respect," she said.

The St James's Garden excavation near Euston station will continue for at least another year, and it is hoped in that time Captain Flinders will be found.